V-Ray 3.30.05 + Max 2016 SP3: Clip opacity mode affects also bump maps

[LudvikKoutny]

Hi,

I've spent last hour stuck wondering why gradient bump map on my leaf material doesn't work whenever I use opacity map, and I've found out that when Opacity mode is set to clip, it clips also bump maps, so that was the reason my gradient bump map did not work. Would be good to get this fixed.

Thanks.

[matanov]

Hi,

Try loading the opacity map through VRayHDRI.

[LudvikKoutny]

Hi,

Try loading the opacity map through VRayHDRI.

I am returning to this thread as this is still not fixed.

I tried loading the opacity map through V-Ray HDRI, and it works, but it's an annoying workaround rather than a solution. I think that bump mapping should not stop working when opacity mode is set to clip with regular Max's bitmap. I do not know many people who use VrayHDRI for something like opacity maps. Also, opacity has nothing to do with bump mapping, so it should not affect it, let alone make it stop working

[matanov]

I've bumped the issue in our bug tracking system.

[cheerioboy]

I just ran into this issue. But loading the opacity map into a VRayHDRI did solve it.

[Alex_M]

This issue still persists with Vray 3.40.02. Setting opacity to "Clip" mode disables bump mapping. The HDRI workaround works, thankfully. Maybe this limitation and the HDRI workaround should be mentioned in the help pages. Otherwise people might think that they can not have bump maps at all with Clip mode and that would be a pity since it saves a lot of time when rendering objects like leaves, grills etc.

[Zdravko.Keremidchiev]

Thank you for the update and the suggestion, we will consider your idea. Generally the issue have Major priority so it should be fixed soon.

[Komposer]

sorry, it´s not my forum but let me ask this:
1. is it planned that the Clip function becomes part of Vray for Maya?
2. is in Maya an equivalend of VRay HDRI loader? Which seem´s to fix the horror rendertimes with opacity mapped leafes...
3. When Clip works, how many rendertime saving is possible? Let´s say now in Maya it renders 10min (instead of 1min30 with a non mapped tree )
Thanks

[vlado]

1. is it planned that the Clip function becomes part of Vray for Maya?

2. is in Maya an equivalend of VRay HDRI loader? Which seem´s to fix the horror rendertimes with opacity mapped leafes...

The File node is already an equivalent of VRayHDRI. You can add V-Ray texture filtering attributes to a File node and set the texture filter to "Smooth" and "smooth method" to "Bilinear". See here for more information:
https://docs.chaosgroup.com/display/...-TextureFilter

Best regards,
Vlado

[vlado]

Btw you can also emulate the Clip mode manually using a Condition node - if the alpha mask is less than 0.5, force it to 0.0, otherwise force it to 1.0. If you combine it with the texture filtering override described above, you can get exactly an equivalent of the Clip mode in 3ds Max.

Best regards,
Vlado

[LudvikKoutny]

Btw you can also emulate the Clip mode manually using a Condition node - if the alpha mask is less than 0.5, force it to 0.0, otherwise force it to 1.0. If you combine it with the texture filtering override described above, you can get exactly an equivalent of the Clip mode in 3ds Max.

Best regards,
Vlado

I've been doing something like that already for years in renderers that did not have this option. I just used output map and clamped the curve. The problem of this bug is rather that if you enable clip, you may not even notice your bump mapping has disappeared, and you may notice it only after rendering some high res image and noticing your objects are somewhat flat, and then you will spend another load of time figuring out why is it happening, because clip option that controls opacity is probably one of the last things you'll look into

Unless you are a forum frequenter, this may cause you quite a few headaches, especially under pressure of deadline

EDIT: Nevermind, I did not notice it was comment related to Maya request

[Komposer]

hi Vlado, made some test´s here and can not confirm your hint´s - but perhaps I made a mistake?
1. "The File node is already an equivalent of VRayHDRI" - you mean the normal file tex from maya?
2. I set the texture filter from maya to off and insert the filter like your hint - Renderspeed goes from 2min12 to 2min30!
3. I pluged in the condition node - no difference - but perhaps I set it in a wriong way? (never used before)
btw. the alpha mask has only at the mask edges other values than 0 or 1, sure that the condition node makes sense in such case?
...please see the attached images.
It´s a tree from Evermotion (Vol58, nr35)
Thanks

[Mihail.Djurev]

Hi,
1. Yes, the normal file node. To override filtering you need to add Attributes>V-Ray>Texture filtering and disable texture filtering.
3. The Clip modes for opacity mapping have been requested before in this thread . This in our to-do list for the next V-Ray for Maya release.